chain

a series of objects connected one after the other, usually in the form of a series of metal rings passing through one another, used either for various purposes requiring a flexible tie with high tensile strength, as for hauling, supporting, or confining, or in various ornamental and decorative forms.

2.

Often, chains. something that binds or restrains; bond:

the chain of timidity; the chains of loyalty.

3.

chains.

shackles or fetters:

to place a prisoner in chains.

bondage; servitude:

to live one's life in chains.

Nautical. (in a sailing vessel) the area outboard at the foot of the shrouds of a mast: the customary position of the leadsman in taking soundings.

a distance-measuring device consisting of a chain of 100 links of equal length, having a total length either of 66 feet (20 meters) (Gunter's chain or surveyor's chain) or of 100 feet (30 meters) (engineer's chain)

Figurative use from c.1600. As a type of ornament worn about the neck, from late 14c. Chain of stores is American English, 1846. Chain gang is from 1834; chain reaction is from 1916 in physics, specific nuclear physics sense is from 1938; chain mail first recorded 1822, in Scott, from mail (n.2). Before that, mail alone sufficed. Chain letter recorded from 1892; usually to raise money at first; decried from the start as a nuisance.

Nine out of every ten givers are reluctant and unwilling, and are coerced into giving through the awful fear of "breaking the chain," so that the spirit of charity is woefully absent. ["St. Nicholas" magazine, vol. XXVI, April 1899]

Chain smoker is attested from 1886, originally of Bismarck (who smoked cigars), thus probably a loan-translation of German Kettenraucher. Chain-smoking is from 1930.

v.

late 14c., "to bar with a chain; to put (someone) in chains," also "to link things together," from chain (n.). Related: Chained; chaining.

(chān) A group of atoms, often of the same element, bound together in a line, branched line, or ring to form a molecule. ◇ In a straight chain, each of the constituent atoms is attached to other single atoms, not to groups of atoms. ◇ In a branched chain, side groups are attached to the chain. ◇ In a closed chain, the atoms are arranged in the shape of a ring.

Chain, Sir Ernst Boris 1906-1979.German-born British bacteriologist who, with Howard Florey, developed and purified penicillin in 1939. For this work, they shared a 1945 Nobel Prize with Alexander Fleming, who first discovered the antibiotic in 1928.